The present invention relates to the field of assembly and adjustment of elements requiring high precision alignment. In particular, the invention includes an apparatus and method for aligning, sequencing, and assembling multiple elements requiring high precision alignment that is adaptable for use with different end items.
Construction and maintenance of complex assemblies which require disassembling and reassembling with small tolerances for fit and alignment has been a substantial challenge. A variety of equipment items, for example horn antennas, have required numerous rework activities, as initial assembly results do not meet print specifications. For example, costs associated with existing methods and equipment resulted in multiple rework activities, i.e., tear down, realignment, etc., exceeding funding allowances for overhaul and restoration. One existing approach called for assembly of elements of a multi-element horn antenna on a flat controlled surface that provided a planar datum reference for element body to element body alignment but did not manage or control critical elements of each body, e.g., machined connector hole or connector hole surface. Existing processes and equipment were particularly unsuitable due to use of cast elements which had some degree of variation in body elements which called for shimming or inter-element alignment adjustment after an initial assembly. A need existed for a multi-datum alignment system which permitted an initial assembly, measurement/evaluation of multiple alignment specifications, then a small increment disassembly which permitted small or very small alignment adjustments to be made while permitting other elements of the multi-element assembly to remain fixed in relation to each other. A need also existed to create a process and apparatus which allowed for assembly, measurement/adjustment, and reassembly of the multi-element assembly with final configuration elements such as end caps or other structures which hold the multi-assembly together in an end use configuration. Another need was to create an apparatus which was operable with more than one multi-element assembly so that support equipment requirements were reduced and reconfiguration time and effort were reduced to a minimum.
According to a further illustrative embodiment of the present disclosure, a base plate is coupled with a back plate that is configured with multiple alignment pins adapted to engage with alignment locations of multiple element assembly items, e.g., elements, such that the elements are held in a predetermined orientation with respect to a back plate and base plate. The base plate is further configured to couple to parts of the multiple elements, which are used in end applications, to hold the items together in an end application use. An exemplary apparatus further includes an adjustable compression or clamping mechanism which maintains/releases pressure on the multiple elements against the back plate so as to permit measurements of tolerances of the elements and re-alignment of the elements with respect to each other. The back plate in this embodiment is adapted to hold the alignment pins in a first location when the back plate is in a first orientation for one type of multiple elements, and hold the alignment pins in a second location when the back plate is in a second orientation for a different type of elements. Different types of adjustable compression or clamping mechanisms can be used including a strap run laterally across the elements when positioned in an element stack and around a back side of the back plate opposite of a side facing the element stack, as well as an expansion mechanism, such as a scissor jack having a screw actuator that leverages against a leverage point on the base plate on one side and against a side of the element stack on a side of the element stack opposing an element stack side in contact with the back plate. An embodiment of the invention can also include an adjustable tensioner, such as a turnbuckle, that couples between two finger brackets which insert protrusions of the finger brackets into apertures created by respective multiple elements in a final configuration on opposing ends of the element stack.
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiment exemplifying the best mode of carrying out the invention as presently perceived.